Specifically, the computer repair company Rescuecom charges that its trademark is violated when business rivals use its name to trigger paid search ads.

The case is nearly identical to a lawsuit brought by insurance company Geico. In that case, a trial judge in December 2004 decided the key issue in Google's favor. Midway through trial, federal district court Judge Leonie Brinkema ruled that Google's practice of allowing Geico rivals to display ads when people type "Geico" into the search box didn't violate trademark law because it didn't lead to consumer confusion.

Rescuecom also lost at the district court level but, unlike Geico, appealed the decision. With the case now pending in the Second Circuit, the civil rights group Electronic Frontier Foundation has gotten involved. In a friend-of-the-court brief filed this week, the EFF argues that there's more at stake than just competition between business rivals. The EFF makes the case that Google's policy of allowing people to purchase trademarked names also protects free speech rights.

For instance, the group says, the advocacy group "The Coalition of Immokalee Farm workers" recently purchased search ads on the word "McDonald's" as part of a push to rally support for better wages at the fast food chain. "This is an example of the important free speech activity that search engines help facilitate," writes the EFF in its brief.

For reasons that aren't entirely clear, as of this morning, no paid search ads appeared in the Google results for searches on "McDonald's." Still, the point is valid. People use search engines to discover information not just about companies, but also about their competitors and critics. It's easy to understand why some companies might not be happy with this state of affairs, but their recourse is to offer better or cheaper goods or services, or to counter critics with arguments, as opposed to filing trademark infringement lawsuits.